# -*- coding: utf-8 -*-
# @Time    : 2023/11/12
# @Author  : Yangyali
#
import pygame
from pygame.sprite import Sprite
class Ship:
    """A class to manage the ship."""

    def __init__(self, ai_game): #ship类的属性是AlienInvasion的实例
        """Initialize the ship and set its starting position."""
        super().__init__()
        self.screen = ai_game.screen
        self.settings = ai_game.settings
        self.screen_rect = ai_game.screen.get_rect()


        # 加载ship的图像
        self.image = pygame.image.load('images/ship.bmp')
        self.rect = self.image.get_rect()

        # 每搜新飞船，都将其放在屏幕底部的中央
        self.rect.midbottom = self.screen_rect.midbottom
        #移动标志
        self.moving_right = False
        self.moving_left = False

        #在飞船的属性x中存储小数值
        self.x = float(self.rect.x)


    def blitme(self):
        """在指定位置绘制飞船."""
        self.screen.blit(self.image, self.rect)

    def update(self):
        """根据移动标志调整飞船位置"""
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.x += self.settings.ship_speed
        if self.moving_left and self.rect.left > 0:
            self.x -= self.settings.ship_speed
        #根据self.x更新rect对象
        self.rect.x = self.x
    def center_ship(self):
        """让飞船在屏幕底端居中"""
        self.rect.midbottom = self.screen_rect.midbottom
        self.x =float(self.rect.x)
